Atmospheric pressure equalizing means



United States Patent 3,521,546 ATMOSPHEREC PRESSURE EQUALIZING MEANSLeslie Day, Chicago, Ill, assignor to Vacuum Concrete (Overseas) Co.Est, Vaduz, Liechtenstein, a corporation of Liechtenstein Filed Mar. 1,1967, Ser. No. 619,792 Int. Cl. F24f 13/10; F16k 17/18 US. Cl. 9832Claims ABSTRACT OF THE DISCLOSURE Means for automatically equalizing airpressure between that within a building and atmosphere when there is asudden and/or extreme drop in atmospheric pressure in the vicinity ofthe building. The equalizing means provides normal ventilation air flowthrough said means in accordance with the normal relatively slightchanges in atmospheric pressure causing differential of pressure betweenthat within the building and atmosphere as well as providing means forthe return to normal of the air pressure within the structure as theatmospheric pressure returns to normal after the passage of the extremelow pressure area. Accordingly, the abnormal and/ or destructiveinwardly acting pressure on the walls and roof of the building isavoided.

While the invention has particular utility embodied in buildings, forautomatically equalizing the interior pressures and atmosphere wherethere is a sudden and/or severe drop in atmospheric pressure, it is tobe understood that its utility is not confined thereto.

As is well known, much of the destruction caused by twisters, tornadoes,cyclones or other high velocity winds is due to buildings exploding as aresult of the sudden and great drop or reduction in the atmosphericpressure in the vicinity of the buildings, in the path of suchtornadoes, cyclones, twisters, or other high velocity winds.

It is known that the eye of a twister is at a greatly reduced barometricair pressure as it moves ahead in its path. The air in the buildings isat normal pressure which may vary from approximately 28 to 32 of mercuryor about 2 pounds per square inch of surface, and this air at normalpressure is trapped inside the buildings when the twister arrives withits lower air pressure. This creates an unbalanced outwardly actingpressure in the buildings which causes weaker structures to explode. Thegreater the differential of air pressure inside the structures ascompared with the outside or atmospheric pressure the greater and moredestructive the explosion.

The present invention solves the problem and overcomes the difiicultiesthereof by providing means operative under and responsive to the outwardpressure within a building to permit the higher pressure in saidbuilding to exhaust outwardly and harmlessly through valve meanscomprising unevenly balanced louver boards or vanes which are normallyclosed but which tilt upwardly to increase the effective size of theopening and allow maximum escape of interior air. While the louvers arenormally closed, they do not seal the opening they control but areloosely enough disposed to permit the passage of air through the openingfor normal ventilation and normal slow changes in atmospheric pressure.

Also contemplated by the present invention is means to relieve orrelease pressures in lower stories of multiple story buildings as wellas the pressure in the upper story or in the attic. A pressure reliefmeans, which may comprise a single louver board or vane in the ceilingof lower floor rooms for controlling an opening in such ceiling to allowthe higher pressure air to escape into the attic and then out throughthe attic louvers.

3,521,546 Patented July 21, 1970 In summation, the present inventionallows air under normal conditions to enter or leave the building toprovide pressure equalization between the interior of the building andatmosphere and thereby provide normal ventilation. However,,underabnormal conditions of an act of nature, such as a twister, cyclone,tornado or the like which suddenly and violently reduces the atmosphericair pressure, the higher pressure air in the building is allowed toquickly escape and prevent the building from exploding. The inventionalso provides means for the return to normal of the air pressure Withinthe structure as the atmosphere returns to normal after the passage ofthe extreme low pressure area, thereby avoiding abnormal inwardly actingpressure on walls and roof of the building.

It is, therefore, an object of the invention to provide means forpreventing buildings from exploding when there is a sudden andrelatively great reduction of atmospheric pressure.

It is another object of the present invention to provide air pressurerelief or equalizing means for permitting excessive air pressure withina building to escape to atmosphere upon a sudden and great drop inatmospheric pressure, and a corresponding return to normal air pressurewithin the building as atmospheric pressure returns to normal.

It is still another object of the invention to provide means of thischaracter that permits normal breathing of air into and out of thestructure with gradual changes in atmospheric pressure such as occursunder normal weather conditions.

It is a further object of the invention to provide means of thischaracter that provides ventilation for the building under normalweather and atmospheric conditions.

It is a still further object of the invention to provide means of thischaracter that prevents rain, or snow from entering the building.

It is another object of the invention to provide means of this characterthat is simple in construction and reliable and effective in operation.

Still another object of the invention is to provide means of thischaracter that is relatively inexpensive to manufacture and to install.

These and other objects of the invention are achieved by providing aframe defining an opening in which a plurality of louver boards or vanesare mounted in an unbalanced condition so that they are normally in theclosed position whereat they will permit ventilation through the framedopening and will prevent entrance of rain or snow but will swing open topermit rapid exhausting of excessive air pressure should there be asudden and great drop in atmospheric pressure in the vicinity of thebuilding caused by an abnormal weather condition such as a twister,tornado, cyclone or the like.

There is also contemplated by the present invention, pressure reliefmeans for lower stories of multiple story buildings. This pressurerelief means may comprise one or more pivoted louver boards or vanesunbalanced to be normally closed, and which, when opened by adilferential of air pressure permits the air from such lower story toescape either to the upper story or attic of the building from which itis vented to atmosphere.

The characteristics and advantages of the invention are furthersufficiently referred to in connection with the following detaileddescription of the accompanying drawings which represent one embodiment.After considering this example, skilled persons will understand thatmany variations may be made Without departing from the principlesdisclosed, and I contemplate the employment of any structures,arrangements or modes of operation that are properly within the scope ofthe appended claims.

Referring to the drawings, which are for illustrative purposes only:

FIG. 1 is a perspective view of a portion of a building embodying thepresent invention;

FIG. 2 is an enlarged sectional view taken on line 22. of FIG. 1;

FIG. 3 is a similar view of an alternative arrangement of the louverscontrolling the vent opening;

FIG. 4 is an enlarged sectional view taken on line 44 of FIG. 1;

FIG. 5 is a sectional view taken on line 55 of FIG. 4; and

FIG. 6 is a sectional view of an alternative arrange ment of the ventcontrol means.

Referring more particularly to FIG. 1 there is shown a building,indicated generally at 10, having pressure relief or atmosphericpressure equalizer means, indicated generally at 12, for the attic ofthe structure. There is also a pressure relief or equalizer means,indicated generally at 14, for equalizing the pressure between the topstory and the attic. An alternative atmospheric pressure equalizer meansis indicated generally at 16, for equalizing the pressure between alower story of a multiple story structure and atmosphere.

The atmospheric pressure equalizer means 12 has a frame provided withtop and bottom frame walls or members 20 and 22, respectively, andvertical side frame walls or members 24 interconnecting the top andbottom frame walls. This frame is incorporated into an outside Wall 26of the building and is so located as to provide what may be termed avent opening 28 for the passage of air between the attic and atmosphere.

In the arrangement shown in FIG. 2 the vent opening 28 is controlled bya plurality of movable fins or vanes 30 spaced apart from each othersaid fins having pivot pins 32 secured thereto at the ends thereof, saidpins being pivotally received in bores provided therefor in the frameside walls 24. Pivot pins 32 are disposed closer to one side of thelongitudinal center of the fins so that said fins are unbalanced. Thelarger parts of the fins are at the outer side and since said largerparts are heavier than the parts of said fins at the opposite side ofthe pivotal axis thereof said outer parts are urged downwardly bygravity. Means for limiting gravity urged movement of the fins isprovided and comprises stop pins fixed in the side frame members orwalls 24, there being a stop pin 38 at each end of each fin. The stoppins 38 are so positioned that the fins or vanes 30 are substantiallyparallel to each other in the frame of the pressure equalizer means 12and when in the normal position said fins thereof are inclined upwardlyand inwardly, as shown in FIG. 2. When the fins are in this normalposition there is sufiicient spacing between them to provide for orpermit normal ventilation through the opening 28 with air passing eitherinwardly or outwardly depending upon whether atmospheric pressure ishigher or lower than the air pressure in the attic. Also this spacing ofthe vanes provides for the rapid return to normal of air pressure withinthe building or structure as the atmospheric pressure returns to normalafter the passage of the extreme low pressure area, thereby preventingan abnormal inwardly acting pressure on walls and roof of the building.

It is to be noted that the upper inner edge of the top fin or vane ispositioned close to the top frame wall or frame member and hence it maybe said that the mechanism is in the closed position when in said normalposition.

A drain board 40 is secured within the frame of the pressure equalizermeans 12 adjacent the bottom thereof, said drain board being inclineddownwardly and outwardly and extending outwardly beyond the outer edgeof the lower or bottom frame member 22. The outer edge of the lower finor vane is normaly close to the adjacent part of the drain board so thatsubstantially no air passes between these parts, normal ventilationbeing through the spaces between the fins or vanes.

Should there be a sudden abnormal drop in atmospheric pressure caused byan act of nature such as a twister, cyclone, tornado or the like thepressure within the structure, particularly within the attic willsuddenly be very much greater than exterior atmospheric pressure and thesudden and great differential of pressure, with the higher pressurewithin the building, will cause the fins or vanes to swing on theirpivotal axis, the parts of the fins at the outer side of said pivotalaxis swinging or pivoting upwardly and the parts at the opposite sidethereof swinging downwardly. Thus the fins will move to the open orpressure relief position and the spacing between said fins will increaseto allow a greater volume of air to flow through the opening 28. Also,the upper fin will swing upwardly to such an extent that there will be asubstantial opening for air between said upper fin and the upper or topframe wall member 20 and the lower fin will move away from the drainboard and provide for escape of air between said bottom fin and saiddrain board. The spacing of the fins or vanes is such that the effectivesize of the opening 28 of the pressure equalizer means will increasesufliciently to relieve any dangerous differential of pressure betweenthat within the structure and atmosphere upon a sudden abnormal drop inatmospheric pressure and thereby prevent an explosion that would damageor destroy the structure.

When in the normal closed position the fins or vanes are inclineddownwardly and outwardly to prevent rain from entering the building. Thesame is true of the drain board 40 which is similarly inclined so thatrain water will drain outwardly.

There is also means provided for flow of high pressure air from thestory of the building below the attic. An alternative pressure equalizerarrangement may be used such as that indicated at 14.

This arrangement is installed in the ceiling of the story of thebuilding just below the attic. Actually an opening is provided in boththe ceiling 44 of the top story and the floor 46 of the attic, saidopenings being in alignment with each other and receive a metal frame,indicated generally at 48.

Frame 48 may be of any suitable shape but is shown as being rectangularwith an outwardly turned peripheral flanges 50 about the top edges ofthe side walls 52 and an end wall 54, the opposite end wall 56 beingwithout a top flange. Top flange 50 rests on the edge portion of theopening in said floor with the side and end walls of said frame 48disposed within the aligned openings in the floor of the attic andceiling of the top story, as shown in FIGS. 4 and 5. Nails 60 or othersuitable means secure the flange 50 to the floor 46 of the attic. Endwall 56 is provided with an inturned flange 62 at its lower edge.

There is a movable equalizer member, indicated generally at 66, saidmember 66 having a panel portion 68, and an upturned flange 70 along theside edges of the panel, said flange being normal to the plane of thepanel 68. There is also an upturned flange 72 along an end edge of thepanel. At the opposite end of the panel there is an edge flange 74 whichis inclined toward the panel end having the flange '72, or said flange74 may be considered as being inclined inwardly.

The equalizer member 66 is pivotally mounted in the frame 48 by means ofaxially aligned pivot pins 78 which have their outer ends secured as bybrazing or welding or the like in openings provided therefor in the sidewalls 52 of the frame 48, said pins being pivotally received in openingsprovided therefor in the side flanges 70. The pins 78 are closer to oneend of the equalizer member than the other end so that the equalizermember is un balanced in such manner that the longer portion normallyrests on the flange 62 of the frame. When there is a differential ofpressure on opposite sides of the equalizer member 66, with the higherpressure at the under side, the equalizer member will swing clockwise,

as shown in FIG. 4, to permit the higher pressure air to pass throughthe frame into the room or attic above. It is to be noted that theinward inclination of the flange 74 provides operable clearance withregard to the adjacent wall of the frame.

A frame 84 may be installed about the frame 48 if desired.

Referring to FIG. 3, the pressure relief or equalizer means 16 has aframe similar to the frame of the arrangernent shown in FIG. 2, saidframe having top and bottom frame walls 20 and 22 and vertical sidewalls or members 24. While this equalizer means is shown as beinginstalled in an autside vertical wall '86, of a lowerstory of thestructure, it is to be understood that it may be installed in the wallportion of another story.

Within the frame of the arrangement of FIG. 3 is a horizontal partition88 separating the frame into upper and lower parts or compartments 90and 92, respectively. This frame is open at the inner end as well as atthe outer end as is the case with the frame of the arrangement shown inFIG. 2.

Both upper and lower portions of the frame have a pluralityof movablefins or vanes 94 which taper from their inner edges to their outeredges, said vanes or fins being thicker at the thickest part adjacenttheir outer edges. Each fin or vane has axially aligned pivot pins 96suitably secured in their ends, said pins being pivotally received insuitable openings provided therefor in the adjacent vertical or sideframe walls. The longitudinal axes of the fins or vanes is offset towardthe smaller, inner edges so that they are unbalanced outwardly, theunbalancing being increased by the additional weight provided by thethicker edge portions.

The pivot pins of the fins or vanes are spaced vertically apart topermit proper movement of the fins or vanes when the interior pressurebecomes greater than the outside pressure. Normally, the outer edges ofthe fins or vanes rest on one another when in the normal closed positionto close the compartments in which said fins or vanes are mounted. It isto be noted that the inner edge portion of the top fin or vane isnormally in contact with the top frame member 20.

While the vanes 94 are in a closed position, it is to be understood thatthey seal the compartments 90 and 92 so there is no seepage of air, rainor snow through the compartments 90 and 92. When interior pressurebecomes greater than exterior pressure the vanes are moved in aclockwise direction by the higher interior pressure air and becomesubstantially parallel to one another thereby providing spacestherebetween to permit the higher pressure air to escape through theframe.

It is to be noted that the inner edge portion of the top fin or vane inthe lower compartment 92 is positioned close to or may be in contactwith the horizontal partition 88 when the vanes in said lowercompartment are in the normal closed position.

The alternative arrangement of FIG. 6 comprises a duct 100 extendingfrom a lower story to an upper story and opening into the upper story,there being a laterally turned part 102 at the lower end defining anopening 104 into the lower story and in which a fin or vane 106 isoperably disposed. Vane 106 is pivotally mounted on pins 108 at oppositeends thereof, said pins being axially aligned on a horizontal axis. Thepins 108 are pivotally mounted in openings provided therefor in the wallof the duct defining the laterally turned portion 102 and said pins arecloser to the upper edge of the vane so that said vane is unbalancedwith the lower portion heavier than the upper portion thereby causingsaid vane to normally be vertically disposed for closing the opening 104when the pressures on opposite sides of said vane are equal. Should theatmospheric pressure suddenly drop and effect opening of the pressurerelief means thereof so that the pressure in the upper storycorrespondingly drops the pressure will be reduced on the inner side ofthe vane 106 and the higher pressure at the opposite side will act onthe lower portion of the vane to cause same to move inwardly and theupper portion of the vane to move outwardly relative to the opening 104thereby permitting high pressure air to flow through said opening 104and upwardly through the duct to the upper story which is alreadysuitably vented to relieve the pressure thereof. The alternate directionof arrows 110 indicates the direction of the air flow when high pressureis being exhausted to atmosphere and/ or the flow in opposite directionwhen the air pressure inside the structure is returning to normal in theevent that said pressure is reduced by the outflow to a point belownormal.

The invention and its attendant advantages will be understood from theforegoing description and it will be apparent that various changes maybe made in the form, construction and arrangement of the parts of theinvention without departing from the spirit and scope thereof orsacrificing its material advantages, the arrangement hereinbeforedescribed being merely by way of example, and I do not wish to berestricted to the specific forms shown or uses mentioned except asdefined in the accompanying claims.

I claim:

1. Atmospheric pressure equalizing means, comprising:

(a) walls defining a vent opening for the flow of air therethrough;

(b) a plurality of spaced apart louver vanes pivotally mounted in saidopening on respective horizontal axes independently of each other, theaxes of said vanes being vertically spaced apart and being closer to oneedge than the other so that each vane has a portion at one side of itsaxis that is larger and heavier than the portion at the opposite sidethereof and therefore is unbalanced with the heavier side urgeddownwardly by gravity, said vanes being moved to an open position by airpressure on their larger sides when there is an unusually large drop inatmospheric pressure;

(c) and means for maintaining the louvers normally partly open with thefree edges of the larger sides spaced apart to permit free inflow andoutflow of air therethrough in both directions for normal ventilationunder normal pressure change conditions.

2. The invention defined by claim 1 wherein the equal izer means isinstalled in a building structure for the passage of air between theinside and outside of the structure, said pressure equalizer means beingopenable by inside air pressure when there is a sudden drop in outsidepressure whereby to equalize inside air pressure with outside airpressure.

3. The invention defined by claim 2 wherein said structure has aplurality of stories, said equalizer means being installed in an outsidewall of one story; and a second equalizer means for controlling in flowbetween stories of the structure, said second equalizer means having amovable control member actuated when there is a differential of pressureon either side of said control member.

4. The invention defined by claim 1, wherein the vent opening isvertically arranged for generally horizontal airflow therethrough andthe last mentioned means comprises stop means for the vanes forpositively limiting gravity urged pivotal movement of said vanes at saidnormal position, said vanes when in said normal position beingsubstantially parallel to each other with venting space between at leastsome of said vanes for normal ventilating airflow through said ventingspaces.

5. The invention defined by claim 3 wherein said structure has meansseparating two stories, said means having a vent opening therethroughfor the passage of air between said stories; and the second equalizermeans includes at least one movable unbalanced panel for controlling theflow of air through said opening between stories; said panel beingpivotally mounted in said opening and movable between a normal positionand an open position by air pressure.

6. In a multistory enclosed structure comprising outside atmospheric andinternal air pressure equalizing means automatically maintaininginternal air pressure equated to external atmospheric pressure arrangedin selected areas of said structure including:

(a) a first equalizer means;

(b) a second equalizer means;

(c) said first and second equalizer means having louver vane meanspivotally mounted therein;

((1) said vane means normally being in a substantially closed positionfor automatic opening response in two directions in accordance to thehigher pressure of a differential of pressures on opposite sides thereoffor increased air flow through said first pressure equalizing means andwhereby internal pressure in said stories is equalized with the externalatmospheric pressure.

I. The invention defined by claim 6, including at least one swingableelement in said first and second atmospheric air pressure equalizingmeans, said element being automatically responsive in an openingdirection to the higher of a differential of pressure on either siderespectively thereof for effecting increased air flow through saidpressure equalizing means.

8. The invention defined by claim 6, wherein said vane means of saidfirst and second atmospheric air pressure equalizing means are gravityurged toward closed position and are openable upon an abnormal change inexternal atmospheric pressure.

9. Atmospheric pressure equalizing means, comprising:

(a) walls defining a vertical vent opening for the flow of airtherethrough;

(b) a plurality of spaced apart vanes pivotally mounted in said openingon horizontal axes, the axes of said vanes being closer to one edge ofthe respective vanes than the other so that each vane has a portion atone side of its axis that is larger and substantially heavier than theportion at the opposite side thereof and therefore is unbalanced withthe heavier side urged in the closing direction by gravity whenatmospheric pressure is normal, said vanes being urged to the openposition by internal air pressure on the larger sides when externalpressure drops;

(c) and means for positively limiting closing movement of the vanes andholding the vanes in a normal partly open position so air can normallyflow freely therethrough inwardly and outwardly with normal relativelyslow changes in air pressure at one side relative to the air pressure atthe opposite side.

10. Atmospheric pressure equalizing means, compris- (a) walls defining avertical vent opening for the flow of air therethrough;

(b) a plurality of spaced apart vanes pivotally mounted in said openingon horizontal axes, the axes of said vanes being closer to one edge ofthe respective vanes than the other so that each vane has a portion atone side of its axis that is larger and substantially heavier than theportion at the opposite side thereof and therefor is unbalanced with theheavier side urged in the closing direction by gravity when atmosphericpressure is normal, the axes of said vanes being spaced vertically apartand said vanes being urged to the open position by internal air pressureon the larger sides when external pressure drops below internalpressure;

(c) and stop means for positively limiting closing movement of the vanesand holding the vanes in a normal partly open position so that air cannormally flow freely therethrough inwardly and outwardly with normalrelatively slow changes in air pressure at one side relative to the airpressure at the opposite side,

((1) said vanes being held by gravity against the stop means with normalrelatively slow changes in air pressure at one side relative to the airpressure at the opposite side but said vanes being moved away from saidstop means to a greater open position upon a sudden and substantial dropin atmospheric air pressure suflicient to cause the higher pressure airat the inner side, acting on the larger and heavier portions of thevanes, to overcome the force of gravity thereon and force said vanes tosaid greater open position and thereby provide an immediate relief ofpressure at the inner side.

References Cited UNITED STATES PATENTS 1,493,655 5/1924 Vernon 981 19 XR1,575,144 3/1926 Bishop 98-119 2,300,273 10/1942 Connell 137493 X-R302,463 7/ 1884 Alexander 98-29 1,706,280 3/1929 Dyer 981 16 2,074,0243/1937 Phail 98121 2,191,774 2/1940 Reed 98116 XR 2,963,956 12/1960 Hill981 16 3,204,585 9/1965 Carlisle 52-1 XR FOREIGN PATENTS 557,545 5/1958Canada. 522,966 4/ 1955 Italy.

MANUEL A. ANTONAKAS, Primary Examiner US. Cl. X.R. 98--74, 121; 521

UNITED STATES PATENT OFFICE CERTIFI-GA'TE OF CORRECTION Patent No.3,521,546 July 21, 1970 Leslie Day It is certified that error appears inthe above identified patent and that said Letters Patent are herebycorrected as shown below:

In the heading to the printed specification, lines 3 to S,

cancel "assignor to Vacuum Concrete (Overseas) Co. Est., Vaduz,Liechtenstein, a corporation of Liechtenstein".

Signed and sealed this 19th day of January 1971.

(SEAL) Attest:

Edward M. Fletcher, 11'. E. JR.

Commissioner of Patents Attesting Officer

